Pump Fluid End with Integrated Web Portion

ABSTRACT

A fluid end block for attachment to a power end of a high pressure reciprocating pump includes a main body portion having an outwardly facing body forward face, an outwardly facing body rear face opposite the body forward face, and opposing side surfaces. A web portion protrudes outwardly from the outwardly facing body forward face. The web portion may have an outwardly facing web forward face and a curvilinear side surface. The web portion may be integral with the main body portion. A plurality of bosses protrude from the web forward face and having a forward facing end. The plurality of bosses may be integral with the main body portion and the web portion. A plunger bore extends through one of the plurality of bosses configured to receive a reciprocating plunger.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of the filing date of U.S. patentapplication No. 61/593,710, filed Feb. 1, 2012, titled “Pump Fluid Endwith Integrated Packing Glands,” the entire disclosure of which isincorporated herein by reference.

TECHNICAL FIELD

This disclosure relates in general to oil field well service pumps, and,in particular, to a high pressure reciprocating pump having integratedweb support.

BACKGROUND OF THE DISCLOSURE

Well service pumps are employed for pumping fluids into wells fortreatment, such as hydraulic fracturing. The flow rates and thepressures are often high; pressures may exceed 10,000 psi. A typicalwell service pump has a power end that connects to a separate fluid endblock with stay rods. The power end reciprocates plungers that strokewithin plunger bores in the fluid end block. A packing gland member isused to seal the interface between the plunger and the fluid end block.

Packing gland members come in a range of standard sizes and are used fordifferent plunger diameters with the same fluid end block. The packinggland member is bolted to the fluid end block. However, a bolt-onpacking gland requires a seal that can create problems. Also, thebolt-on arrangement may create higher stresses in certain areas, leadingto stress fractures. Often, the packing gland is held to the power endvia tie rods. This too can lead to higher stresses in certain areas.

SUMMARY

In a first exemplary aspect, this disclosure is directed to a fluid endblock for attachment to a power end of a high pressure reciprocatingpump. The fluid end block may include a main body portion having aplurality of chambers therein, the main body portion having an outwardlyfacing body forward face, an outwardly facing body rear face oppositethe body forward face, and opposing side surfaces connecting the forwardface and the rear face; a web portion protruding outwardly from theoutwardly facing body forward face, the web portion having an outwardlyfacing web forward face and a curvilinear side surface, the web portionbeing integral with the main body portion; a plurality of bossesprotruding from the web forward face and having a forward facing end,the plurality of bosses being integral with the main body portion andthe web portion; and a plunger bore extending through one of theplurality of bosses configured to receive a reciprocating plunger, theplunger bore extending from the end of said one of the plurality ofbosses to one of the plurality of chambers in the main body portion.

In an exemplary embodiment, the curvilinear side surface comprises aconvex portion concentric with each of the plurality of bosses.

In an exemplary embodiment, the convex portion has a radius greater thana radius of each of the plurality of bosses.

In an exemplary embodiment, the main body portion comprises a tie rodhole disposed adjacent the web portion, the tie rod hole being disposedbetween undulating portions of the web portion.

In an exemplary embodiment, the curvilinear side surface comprises aconcave portion concentric with a diameter of the tie rod hole.

In an exemplary embodiment, the undulating portions are a portion of thecurvilinear side surface.

In an exemplary embodiment, the undulating portions are filletsconnecting the curvilinear side surface of the web portion to the bodyforward face.

In an exemplary embodiment, each of the plurality of bosses has a firstlength measured from the web forward face to the end of the boss, andwherein the web portion has a second length measured from the bodyforward face to the web forward face, the first length being greaterthan the second length.

In an exemplary embodiment, the web portion extends entirely across thebody forward face from one of the opposing side surfaces to the other.

In an exemplary embodiment, the plurality of bosses is aligned in a rowso that a single plane passes through a central axis formed by each ofthe plurality of bosses.

In an exemplary embodiment, the curvilinear side surface of the webportion is perpendicular to the body forward face and perpendicular tothe web forward face.

In an exemplary embodiment, wherein each of the plurality of bossescomprises an outer surface portion having a first diameter adjacent theforward facing end and having a second diameter adjacent the webportion, the second diameter being greater than the first diameter.

In an exemplary embodiment, wherein the curvilinear side surface is anupper side surface, the fluid end block comprising a curvilinear lowerside surface, wherein the curvilinear upper side surface mirrors thecurvilinear lower side surface.

In an exemplary embodiment, the present disclosure is directed to pumpassembly including the fluid end block and a power end including areciprocating plunger extending into the plunger bore.

In an exemplary embodiment, the pump assembly includes tie rodsextending from the power end, past the plurality of bosses, past the webportion, and into tie rod holes in the forward face of the main bodyportion.

In a second exemplary aspect, this disclosure is directed to a fluid endblock for attachment to a power end of a high pressure reciprocatingpump. The fluid end block may include a main body portion having aplurality of chambers therein, the main body portion having an outwardlyfacing body forward face, an outwardly facing rear face opposite thebody forward face, and opposing side surfaces connecting the bodyforward face and the rear face; a plurality of bosses supported by themain body portion and having a forward facing end, the plurality ofbosses being integral with the main body portion and having an outerdiameter at the forward facing end; a web portion protruding outwardlyfrom the outwardly facing body forward face of the main body portion,the web portion having a longitudinal length and a transverse height,the web portion joining each of the plurality of bosses to each other,the transverse height of the web portion being greater than the outerdiameter of the plurality of bosses; and a plunger bore extendingthrough one of the plurality of bosses configured to receive areciprocating plunger, the plunger bore extending from the end of saidone of the plurality of bosses to one of the plurality of chambers inthe main body portion.

In an exemplary embodiment, the web portion comprises a curvilinear sidesurface comprising a convex portion concentric with each of theplurality of bosses.

In an exemplary embodiment, the convex portion of the web portion has aradius greater than a radius of each of the plurality of bosses.

In an exemplary embodiment, the main body portion comprises a tie rodhole disposed adjacent the web portion, the tie rod hole being disposedbetween undulating portions of the web portion.

In an exemplary embodiment, the undulating portions are formed of acurvilinear side portion comprising a concave portion concentric with adiameter of the tie rod hole.

In an exemplary embodiment, the undulating portions are a curvilinearside surfaces.

In an exemplary embodiment, the undulating portions are filletsconnecting a curvilinear side surface of the web to the body forwardface.

In an exemplary embodiment, each of the plurality of bosses has a firstlength measured from the web forward face to the end of the boss, andwherein the web portion has a second length measured from the bodyforward face to the web forward face, the first length being greaterthan the second length.

In an exemplary embodiment, the web portion extends entirely across thebody forward face from one of the opposing side surfaces to the other.

In an exemplary embodiment, the plurality of bosses is aligned in a rowso that a single plane passes through a central axis formed by each ofthe plurality of bosses.

In an exemplary embodiment, the web portion comprises upper and lowerside surfaces and a web forward face, the upper and lower side surfacesbeing perpendicular to the body forward face and perpendicular to theweb forward face.

In an exemplary embodiment, each of the plurality of bosses comprises anouter surface portion having a first diameter adjacent the forwardfacing end and a second diameter adjacent the web portion, the seconddiameter being greater than the first diameter.

In an exemplary embodiment, the web portion comprises curvilinear upperand lower side surfaces and a web forward face, wherein the curvilinearupper side surface mirrors the curvilinear lower side surface.

In an exemplary embodiment, a pump assembly includes the fluid end blockand a power end including a reciprocating plunger extending into theplunger bore.

In an exemplary embodiment, the pump assembly includes tie rodsextending from the power end, past the plurality of bosses, past the webportion, and into tie rod holes in the forward face of the main bodyportion.

In a third exemplary aspect, this disclosure is directed to a fluid endblock for attachment to a power end of a high pressure reciprocatingpump. The fluid end block may include a main body portion having anoutwardly facing body forward face, an outwardly facing rear faceopposite the body forward face, and opposing side surfaces connectingthe body forward face and the rear face, the main body portioncomprising a plurality of tie rod holes configured to receive tie rodsconnecting the fluid end block to the power end of a high pressurereciprocating pump; a web portion protruding outwardly from the bodyforward face of the main body portion, the web portion having ancurvilinear portion adjacent the tie rod holes, the curvilinear portionbeing shaped and disposed so that at least one of the tie rod holes isdisposed between peaks of the curvilinear portion, the web portion beingintegrally formed with the main body portion; a plurality of bosses onthe web portion, the plurality of bosses being integrally formed withthe web portion and the main body portion; and a plunger bore extendingthrough one of the plurality of bosses configured to receive areciprocating plunger.

In an exemplary embodiment, the curvilinear portion comprises a convexportion concentric with each of the plurality of bosses.

In an exemplary embodiment, the convex portion has a radius greater thana radius of each of the plurality of bosses.

In an exemplary embodiment, the curvilinear portion comprises a concaveportion concentric with a diameter of the tie rod hole.

In an exemplary embodiment, the curvilinear portion comprises acurvilinear side surface.

In an exemplary embodiment, wherein the curvilinear portion comprises afillet connecting a side surface of the web portion to the body forwardface.

In an exemplary embodiment, each of the plurality of bosses has an endand the web portion has a forward face, each of the plurality of bosseshaving a first length measured from the web forward face to the end ofthe boss, and the web portion having a second length measured from thebody forward face to the web forward face, the first length beinggreater than the second length.

In an exemplary embodiment, the web portion extends entirely across thebody forward face from one of the opposing side surfaces to the other.

In an exemplary embodiment, the plurality of bosses is aligned in a rowso that a single plane passes through a central axis formed by each ofthe plurality of bosses.

In an exemplary embodiment, the curvilinear portion comprises a sidesurface of the web portion perpendicular to the body forward face.

In an exemplary embodiment, each of the plurality of bosses comprises anouter surface portion having a first diameter adjacent the forwardfacing end and a second diameter adjacent the web portion, the seconddiameter being greater than the first diameter.

In an exemplary embodiment, the curvilinear portion comprises acurvilinear upper side surface and a curvilinear lower side surface,wherein the curvilinear upper side surface mirrors the curvilinear lowerside surface.

In an exemplary embodiment, the web portion is devoid of tie rodreceiving holes.

In an exemplary embodiment, a fluid pump includes the fluid end blockand tie rods extending to the main body so that the bosses are not heldin tension.

In a fourth exemplary aspect, this disclosure is directed to a method ofmanufacturing a fluid end for a pump, including forming from a monolithmaterial, a main body portion having an outwardly facing body forwardface, an outwardly facing body rear face opposite the body forward face,and opposing side surfaces connecting the forward face and the rearface; forming from the monolith material, a web portion protrudingoutwardly from the outwardly facing body forward face, the web portionhaving an outwardly facing web forward face and a curvilinear sidesurface; forming from the monolith material, a plurality of bossesprotruding from the web forward face and having a forward facing end;and forming a plunger bore extending through one of the plurality ofbosses configured to receive a reciprocating plunger.

In an exemplary aspect, forming the web portion comprises shaping thecurvilinear side surface to have a convex portion concentric with eachof the plurality of bosses.

In an exemplary aspect, forming a tie rod hole in a location adjacentthe web portion so that the tie rod hole is disposed between undulatingportions of the web portion.

In a fifth exemplary aspect, this disclosure is directed to a fluid endblock for attachment to a power end of a high pressure reciprocatingpump. The fluid end block may include a main body portion having aplurality of chambers therein, the main body portion having an outwardlyfacing body forward face, an outwardly facing rear face opposite thebody forward face, and opposing side surfaces connecting the bodyforward face and the rear face, the main body portion comprising aplurality of tie rod holes configured to receive tie rods connecting thefluid end block to a power end of a high pressure reciprocating pump; aweb portion protruding outwardly from the outwardly facing body forwardface, the web portion having an outwardly facing web forward face, anupper curvilinear side surface, and a lower curvilinear side surfacemirroring the upper curvilinear side surface, the upper and lowercurvilinear side surfaces having convex and concave portions, the webportion extending continuously from one of the opposing side surfaces ofthe main body portion to the other, and being integrally formed with themain body portion; a plurality of bosses protruding from the web forwardface and having a forward facing end, each of the plurality of bosseshaving an end, a first region of a first diameter adjacent the end, anda second region of a second diameter adjacent the web portion, thesecond diameter being greater than the first diameter, the plurality ofbosses being integral with the main body portion and the web portion,and wherein the convex portions of the upper and lower curvilinear sidesurfaces are concentric with the second region of each of the pluralityof bosses, and wherein the concave portions of the upper and lowercurvilinear side surfaces accommodate the tie rod holes so that the tierod holes are disposed between portions of the web portion; and aplunger bore extending through one of the plurality of bosses configuredto receive a reciprocating plunger, the plunger bore extending from theend of one of the plurality of bosses to one of the plurality ofchambers in the main body portion.

In an exemplary embodiment, the tie rod holes are disposed betweenportions of a fillet connecting the curvilinear side surface of the webportion to the body forward face.

In an exemplary embodiment, the tie rod holes are disposed betweenportions of the curvilinear upper side surface of the web portion.

In an exemplary embodiment, the concave portions of the curvilinearupper and lower side surfaces are concentric with a diameter of the tierod holes.

In an exemplary embodiment, each of the plurality of bosses has a firstlength measured from the web forward face to the end of the boss, andwherein the web portion has a second length measured from the bodyforward face to the web forward face, the first length being greaterthan the second length.

In an exemplary embodiment, the curvilinear side surface of the webportion is perpendicular to the body forward face and perpendicular tothe web forward face.

In an exemplary embodiment, a pump assembly includes the fluid end blockand a power end including a reciprocating plunger extending into theplunger bore.

In an exemplary embodiment, the pump assembly includes tie rodsextending from the power end, past the plurality of bosses and past theweb portion and into tie rod holes in the forward face of the main bodyportion.

In a sixth exemplary aspect, this disclosure is directed to a pumpsubassembly that includes a fluid end block having forward and rearwardsides; a plurality of bosses protruding in a forward direction from theforward side, the fluid end block and the bosses being a single-piecesteel alloy member; a plunger bore extending into the fluid end blockfrom each of the bosses for receiving a reciprocating plunger, each ofthe plunger bores having a forward end with a set of internal threads;and a plurality of webs protruding from the forward side and joiningadjacent ones of the bosses to each other.

In an exemplary embodiment, the webs are an integral part of thesingle-piece steel alloy member along with the bosses and the fluid endblock; and wherein each of the webs having an upper side and a lowerside and a dimension between the upper and lower sides that is nogreater than an outer diameter of each of the bosses.

In an exemplary embodiment, wherein a horizontal line bisecting each ofthe webs also intersects an axis of each of the plunger bores.

In an exemplary embodiment, the pump subassembly includes a filletjoining a base of each of each of the bosses with the forward side ofthe fluid end block; wherein a wall thickness of each of the bases fromthe base to the counter bore over the radius of each of the fillets isin a range of from about 1.0 to about 2.25.

In an exemplary embodiment, the pump subassembly includes a web upperfillet joining the upper side of each of the webs with the forward sideof the fluid end block; a web lower fillet joining the lower side ofeach of the webs with the forward side of the fluid end block; a bossupper fillet extending partially around each of the bosses and joiningan upper circumferential portion of each of the bosses with the forwardside of the fluid end block, each of the boss upper fillets having anend that joins an end of one of the web upper fillets, such that the webupper fillets and the boss upper fillets define a continuous upperfillet extending across the bosses; and a boss lower fillet extendingpartially around each of the bosses and joining a lower circumferentialportion of each of the bosses with the forward side of the fluid endblock, each of the boss lower fillets having an end that joins an end ofone of the web lower fillets, such that the web lower fillets and theboss lower fillets define a continuous lower fillet extending across thebosses.

In an exemplary embodiment, each of the webs has a forward side that isa distance from the forward side of the fluid end block that is lessthan a distance from a forward end of each of the bosses to the forwardside of the fluid end block.

In an exemplary embodiment, each of the bosses has a cylindrical forwardend portion extending from a cylindrical base having a diameter greaterthan a diameter of the forward end portion; and a distance from aforward end of each of the bosses to the forward side of the fluid endblock over a width of the base is in the range of from about 1.750 toabout 1.944.

In an exemplary embodiment, the bosses comprise an outboard bossadjacent to each outboard side of the fluid end block and at least oneintermediate boss located between the outboard bosses; and the fluid endblock further comprises: a pair of outboard webs, each outboard webextending from one of the outboard bosses to one of the outboard sidesof the fluid end; and each of the outboard webs having an upper side anda lower side and a dimension between the upper and lower sides that isno greater than an outer diameter of each of the outboard bosses.

In an exemplary embodiment, the pump subassembly includes a plurality ofstay rod threaded holes extending into the fluid end block from theforward side; and wherein the forward end of each of the bosses islocated forward from an entrance of each of the stay rod threaded holes.

In a sixth exemplary aspect, this disclosure is directed to a pumpsubassembly that includes a fluid end block having forward and rearwardsides, two outboard sides, a bottom, and a top; a plurality of bossesprotruding in a forward direction from the forward side, the bossescomprising an outboard boss adjacent each of the outboard sides, and atleast one intermediate boss located between the outboard bosses; aplunger bore extending into the fluid end block from each of the bossesfor receiving a reciprocating plunger, each of the plunger bores havinga forward end with internal threads; a web extending from the forwardside of the fluid end block, the web having an outboard portionextending from each of the outboard sides to each of the outboardbosses, the web having an intermediate portion extending betweenadjacent ones of the bosses; the web having an upper side and a lowerside, with a dimension between the upper and lower sides that is lessthan an outer diameter of any one of the bosses; and wherein the fluidend block, the bosses and the webs are integrally joined to each otherand comprise a single-piece member formed of a steel alloy.

In an exemplary embodiment the web has a forward face that is locatedforward from the forward side of the fluid end block a distance that isless than a distance from the forward end of each of the bosses to theforward side of the fluid end block.

In an exemplary embodiment, the subassembly includes a continuous upperfillet extending without interruption from one of the outboard sides tothe other of the outboard sides, the upper fillet joining the uppersides of the web to the forward side of the fluid end block and joiningupper circumferential portions of the bosses to the forward side; and acontinuous lower fillet extending without interruption from one of theoutboard sides to the other of the outboard sides, the lower filletjoining the tower sides of the web to the forward side of the fluid endblock and joining lower circumferential portions of the bosses to theforward side.

In an exemplary embodiment, each of the plunger bores has a counter borefor receiving a packing; each of the bosses has a wall thicknessmeasured from a base of the boss to the counter bore; and a ratio of thewall thickness over a radius of each of the fillets is in a range offrom about 1.0 to about 2.25.

In a seventh exemplary aspect, the present disclosure is directed to awell service pump including a power end having a crankshaft and aplurality of connecting rods; a fluid end block having forward andrearward sides, two outboard sides, a bottom, and a top; a plurality ofbosses protruding in a forward direction from the forward side of thefluid end block, the bosses comprising an outboard boss adjacent each ofthe outboard sides, and at least one intermediate boss located betweenthe outboard bosses; a web extending from the forward side of the fluidend block, the web having an outboard portion extending from each of theoutboard sides to each of the outboard bosses, the web having anintermediate portion extending between adjacent ones of the bosses; aplunger bore extending into the fluid end block from each of the bosses,each of the plunger bores having a forward end with internal threads; aplurality of plungers, each of the plungers being operably coupled toone of the connecting rods for stroking movement within one of theplunger bores; a packing surrounding each of the plungers within each ofthe plunger bores; an externally threaded retainer nut that engages theinternal threads of each of the plunger bores for energizing each of thepackings; a plurality of stay rods extending from the power end tothreaded holes foamed in the forward side of the fluid end block, thethreaded holes having entrances spaced a distance rearward from forwardends of the bosses; and wherein the fluid end block and the bosses areintegrally joined to each other and comprise a single-piece memberformed of a steel alloy.

In an exemplary embodiment, the web has an upper side and a lower sidewith a dimension between the upper and lower sides that is less than anouter diameter of any one of the bosses; and wherein the web isintegrally joined to the fluid end block and the bosses and forms a partof the single-piece member formed of a steel alloy.

In an exemplary embodiment, the pump includes a continuous upper filletextending without interruption from one of the outboard sides to theother of the outboard sides, the upper fillet joining the upper sides ofthe web to the forward side of the fluid end block and joining uppercircumferential portions of the bosses to the forward side of the fluidend block; and a continuous lower fillet extending without interruptionfrom one of the outboard sides to the other of the outboard sides, thelower fillet joining the lower sides of the web to the forward side andjoining lower circumferential portions of the bosses to the forward sideof the fluid end block.

In a seventh exemplary aspect, the present disclosure is directed to amethod of manufacturing a fluid end assembly of a reciprocating wellservice pump. The method may include (a) providing a single-pieceforging of a steel alloy with a plurality of bosses protruding from aforward side of the single-piece forging, and providing a web in thesingle-piece forging extending between adjacent ones of the bosses andfrom outboard ones of the bosses to outboard sides of the single-pieceforging, and (b) machining the single-piece forging into a configurationof a fluid-end block with a plunger bore having internal threads in eachof the bosses.

In an exemplary aspect, each of the webs having an upper side and alower side with a distance between the upper and lower sides being lessthan an outer diameter of each of the bosses.

In an exemplary aspect, step (a) further comprises: providing thesingle-piece forging with a continuous upper fillet extending withoutinterruption from one of the outboard sides to the other of the outboardsides of the single-piece forging, the upper fillet joining the uppersides of the web to the forward side of the single-piece forging andjoining upper circumferential portions of the bosses to the forward sideof the single-piece forging; and providing the single-piece forging witha continuous lower fillet extending without interruption from one of theoutboard sides to the other of the outboard sides, the lower filletjoining the lower sides of the web to the forward side of thesingle-piece forging and joining lower circumferential portions of thebosses to the forward side of the single-piece forging.

Other aspects, features, and advantages will become apparent from thefollowing detailed description when taken in conjunction with theaccompanying drawings, which are a part of this disclosure and whichillustrate, by way of example, principles of the inventions disclosed.

DESCRIPTION OF FIGURES

The accompanying drawings facilitate an understanding of the variousembodiments.

FIG. 1 is an elevational view of a reciprocating well service pumpassembly according to an exemplary embodiment, the pump assemblyincluding a fluid end block.

FIG. 2 is a perspective view of the fluid end block of the well servicepump of FIG. 1 according to an exemplary embodiment.

FIG. 3 is a front view of the fluid end block of the well service pumpof FIG. 1 according to an exemplary embodiment.

FIG. 4 is a side view of the fluid end block of the well service pump ofFIG. 1 according to an exemplary embodiment.

FIG. 5 is a top view of the fluid end block of the well service pump ofFIG. 1 according to an exemplary embodiment.

FIG. 6 is an enlarged sectional view of a portion of the fluid end ofthe well service pump of FIG. 1 according to an exemplary embodiment.

FIG. 7 is a perspective view of another embodiment of a fluid end blockusable on the well service pump of FIG. 1 according to an exemplaryembodiment.

FIG. 8 is a front view of the fluid end block of the well service pumpof FIG. 7 according to an exemplary embodiment.

FIG. 9 is a sectional view of a portion of the fluid end of the wellservice pump of FIG. 7 according to an exemplary embodiment.

FIG. 10 is a perspective view of another embodiment of a fluid end blockusable on the well service pump of FIG. 1 according to an exemplaryembodiment.

FIG. 11 is a front view of the fluid end block of the well service pumpof FIG. 10 according to an exemplary embodiment.

DETAILED DESCRIPTION

FIG. 1 shows a partial cross-sectional view of a high pressurereciprocating pump 100 according to an exemplary embodiment consistentwith the principles disclosed herein. The high pressure reciprocatingpump 100 may be a suitable pump for performing high pressure fracingoperations, and may be used to obtain pressures of 15000 psi or more.The high pressure reciprocating pump 100 includes a power end 102 and afluid end 103 having a fluid end block 104. Stay rods 106 connect thepower end 102 to a forward facing side of the fluid end block 104. Thefluid end block 104 has a plurality of chambers formed therein,including a plurality of cylinder chambers 108 (only one shown in FIG.1). Each of the cylinder chambers 108 is in communication with a suctionmanifold 110 and a discharge port 112. A suction cover plate 114connects to an end of each cylinder chamber 108 on a rearward side ofthe fluid-end 104 opposite the stay rods 106. A suction valve 116 opensthe cylinder chamber 108 to the suction manifold 110 during the intakestroke. A discharge valve 118 opens the discharge port 112 of thecylinder chamber 108 during the discharge stroke.

The pump 100 can be free-standing on the ground, can be mounted to atrailer that can be towed between operational sites, or mounted to askid such as for offshore operations. The power end 102 includes acrankshaft 122, which is rotated by a bull gear 124. A pinion gear 126engages the bull gear 124. A power source such as an engine (not shown)connects to the pinion gear 126 to cause the bull gear 124 to rotate. Aconnecting rod 128 rotatably connects to the crankshaft 122. Theconnecting rod 128 has a wrist pin end 130 opposite from a bearing end,which connects to the crankshaft 122. The wrist pin end 130 pivotallyconnects to a crosshead 132. The crosshead 132 is constrained to linearmovement due to being mounted within a stationary crosshead housing 134.The rotation of crankshaft 122 thus causes crosshead 132 to reciprocate.A pony rod 136 connects to the crosshead 132. The pony rod 136 has anopposite end connected to a plunger 138. In some instances, the plunger138 will connect directly to the crosshead 132, eliminating the pony rod136.

The plunger 138 extends through a plunger bore 150 in the fluid endblock 104 that leads to the cylinder chamber 108. The suction anddischarge valves 116 and 118 in the fluid end block 104 are usuallyactuated by a predetermined differential pressure. The suction valve 116as an inlet valve actuates to control fluid flow through the suctionmanifold 110 into the cylinder chamber 108, and the discharge valve 118as an outlet valve actuates to control fluid flow through the dischargeport 112 from the cylinder chamber 108. The plunger 138 may be one of aplurality of plungers. Depending upon the embodiment, three or fiveplungers 138 may be utilized depending on the size of the pump 100.Other embodiments have a different number of plunger bores 150 and acorresponding number of plungers 138. A packing 152 is mounted withinthe plunger bore 150 to seal against the outer diameter of plunger 138.In the exemplary embodiment disclosed, the packing 152 is retained inposition by a threaded retainer nut 154.

FIGS. 2-5 show an exemplary embodiment of the fluid end block 104 thatforms a part of the fluid end 103 in FIG. 1. In this embodiment, thefluid end block 104 has three bores, and may be referred to as a triplexfluid end. In alternate embodiments, the fluid end block can have fivebores and is called a “quint” or a quintuplex fluid end. Other fluid endblocks have other numbers of bores.

Referring to FIG. 2 the fluid end block 104 is shown in more detail thanthe schematic representation in FIG. 1. The fluid end block 104 has amain body portion 156 having a forward face or forward side 160, arearward side 162, outboard sides 164, a bottom 166, and a top 168. Inthe exemplary embodiment shown, the forward side 160 is generally flatand optionally may have at least two stepped recessed portions 160 a and160 b on its upper section. The stepped upper portions 160 a and 160 bmay also be flat. The first stepped upper portion 160 a is located in aplane parallel and rearward of a plane containing the forward side 160.The second stepped upper portion 160 b extends upward from the firststepped upper portion 160 a and is located in a plane parallel andrearward of the plane containing the first stepped upper portion 160 a.The forward side 160 may also have a stepped lower portion 160 c, whichis in a plane parallel with and recessed from forward side 160. Thefluid end block 104 also has the rearward side 162 facing in a directionopposite the forward side 160. The fluid end block 104 has the twooutboard sides 164 that are orthogonal to the forward side 160 and facein opposite directions. The bottom 166 and the top 168 join the forwardand rearward sides 160, 162. Access ports 170 are provided forinstalling and removing valves 116, 118 (FIG. 1) and extend through thetop 168. The discharge port 112 is located on one of the outboard sides164. Threaded stay rod holes 172 for securing stay rods 106 (FIG. 1) arelocated on the forward side 160.

Bosses 176 are integrally formed with fluid end block 104 and protrudefrom the forward side 160. The bosses 176 include an outboard boss 176 anear each outboard side 164 and at least one intermediate boss 176 blocated between the two outboard bosses 176 a. In this example, there isonly one intermediate boss 176 b. In other embodiments, there are morethan one intermediate bosses such as, but not limited to two, three,four, or more intermediate bosses. Each boss 176 is a generallycylindrical member having a forward end 178 that is forward of the fluidend forward side 160. Each boss 176 has one of the plunger bores 150extending into the fluid end block 104 from the forward end 178. A setof threads 180, preferably internal, is formed in each plunger bore 150at the forward end 178. Optionally, each boss 176 may have a cylindricalbase portion 182 that has a larger outer diameter than a cylindricalforward portion 184.

Referring also to FIG. 3, a web 190 is integrally formed on the fluidend forward side 160 and joins the bosses 176. The web 190 is a bandthat extends from one outboard side 164 to the other, except forintersections with bosses 176, and which protrudes from the fluid endblock forward side 160. The web 190 includes two outboard portions 190a, each of which extends from one of the outboard bosses 176 a to one ofthe outboard sides 164. The web 190 also has two intermediate portions190 b, each of which extends from intermediate boss 176 b to one of theoutboard bosses 176 a. The web 190 has an upper side 192 and a lowerside 194 that have straight as well as curvilinear portions. A plane 196is shown in FIG. 3. The plane 196 passes through the web 190 from oneoutboard side 164 to the other outboard side and equidistant between theupper and lower sides 192, 194 and also passes through each axis 198 ofeach plunger bore 150. The web 190 has a forward face 200 that in thisembodiment is flat and parallel with the boss forward ends 178 and thefluid end block forward side 160.

The upper side 192 and the lower side 194 each form curvilinear surfacesundulating between tie rod holes 172 and the bosses 176. As such, theweb 190 is devoid of tie rod holes. These upper and lower sides 192, 194of the web 190 are formed to be substantially perpendicular to the faceof the forward side 160. The upper side 192 includes two outboardportions 192 a, each having an end joining one of the outboard sides164, includes circumferential portions 192 b extending convexlypartially around an upper portion of each boss 176, and includesintermediate portions 192 c each extending concavely between the uppercircumferential portions 192 b. In the embodiment shown, the convexportions form peaks and the concave portions form valleys. In theembodiment shown, the lower side 194 is a mirror image of the upper sideand includes two outboard portions 194 a, each having an end joining oneof the outboard sides 164, includes circumferential portions 194 bextending convexly partially around an upper portion of each boss 176,and includes intermediate portions 194 c each extending concavelybetween the upper circumferential portions 194 b.

In some embodiments, the upper and lower circumferential portions 192 b,194 b are convexly curved surfaces concentric with the diameter of thebosses 176. In the embodiment disclosed herein, the intermediateportions 192 c, 194 c are concavely curved surfaces are non-concentricwith the diameter of the tie rod holes 172, but smoothly connect theconcavely curved surfaces of the circumferential portions 192 b, 194 b.In other embodiments, the profile of the upper and lower sides 192, 194varies to be either greater or less than that described herein,depending upon the size and positions of the bosses 176 and tie rodsholes 172. Furthermore, in some embodiments, the upper and lower sides192, 194 are not mirror images of each other.

An upper fillet 204 joins the web upper side 192 to the fluid endforward side 160. The upper fillet 204 is a curved surface extendingcontinuously from one outboard side 164 to the other. The upper fillet204 has two outboard portions 204 a, each having an end joining one ofthe outboard sides 164. Each fillet outboard portion 204 a joins theupper side 192 of the outboard web portion 190 a to the fluid end blockforward side 160, which is in a plane 90 degrees relative to a planecontaining the upper sides 192 of the web outboard portions 190 a. Anupper fillet circumferential portion 204 b extends partially around anupper portion of each boss 176. The upper fillet circumferential portion204 b is a curved surface joining an upper portion of the outer diameterof each boss 176 to the fluid end block forward side 160. In thisexample, the upper fillet circumferential portion 204 b extends about115 degrees about the plunger axis 198, but the extent may vary. In thisexemplary embodiment, there are two upper intermediate fillet portions204 c, each extending from an end of the upper circumferential filletportions 204 b to an end of the adjacent upper circumferential filletportion. The upper intermediate fillet portions 204 c are generallyU-shaped, with the legs of the “U” extending upward. The upperintermediate fillet portions 204 c are curved surfaces joining theintermediate web portions 190 b to the forward side 160 of the fluid endblock. Accordingly, in the embodiment shown, the upper circumferentialportions form peaks and the intermediate fillet portions form valleys.The outboard portions 204 a, circumferential portions 204 b, andintermediate portions 204 c form the continuous upper fillet 204extending from one fluid end outboard side 164 to the other.

A lower fillet 210 is an inverted image of the upper fillet 204 andjoins the lower side 194 of the web 190 to the forward side 160 of thefluid end block 104. The lower fillet 210 is a curved surface extendingcontinuously from one outboard side 164 to the other. The lower fillet210 has two outboard portions 210 a, each having an end joining one ofthe outboard sides 164. Each fillet outboard portion 210 a joins thelower side 194 of the outboard web portion 190 a to the fluid end blockforward side 160, which is in a plane 90 degrees relative to a planecontaining the lower sides 194 of the outboard portions 190 a. A lowerfillet circumferential portion 210 b extends partially around a lowerportion of each boss 176. The lower fillet circumferential portion 210 bis a curved surface joining a lower portion of the outer diameter ofeach boss 176 to the forward side 160 of the fluid end block. In thisexample, the lower fillet circumferential portion 210 b extends about115 degrees about plunger axis 198, but the extent may vary. There aretwo lower intermediate fillet portions 210 c, each extending from an endof the lower circumferential fillet portions 210 b to an end of theadjacent lower circumferential fillet portion.

The lower intermediate fillet portions 210 c are generally U-shaped,with the legs of the “U” extending downward. The lower intermediatefillet portions 210 c are curved surfaces joining intermediate webportions 190 b to the fluid end block forward side 160. The outboardportions 210 a, circumferential portions 210 b, and intermediateportions 210 c form the continuous lower fillet 210 extending from onefluid end block outboard side 164 to the other. The upper and lowerfillets 204, 210 do not contact each other.

Referring to FIG. 4, the forward end 178 of each boss 176 is located adistance L from the forward side 160 of the fluid end block 104. Thedistance L may vary, but will typically be greater than one half of theouter diameter D of the forward portion 184 of each boss 176. In thisexample, distance L is about 80% of the outer diameter D. In someembodiments, the distance L may be a distance within a range of about 5in. to 15 in., while in other embodiments, the distance L may be adistance within a range of about 6 in. to 8 in. In one embodiment, thedimension L is about 7 in. Other distances are contemplated. Thedistance L is also proportional to a length of the stroke of plunger 138(FIG. 1). A long stroke for plunger 138 will result in a greaterdistance L. The forward face 200 of the web 190 is located a distance Wfrom the forward side 160 of the fluid end block 104. The distance W isless than the distance L and in another embodiment the distance W isless than one-half of the distance L. In this example, the distance W isabout 35% of the distance L, but it may vary. The distance W, which canbe the width of the web 190, is preferably the same in the web outboardportions 190 a and the intermediate portions 190 b. In some embodiments,the distance W may be a distance within a range of about 1 in. to 6 in.,while in other embodiments, the distance W may be a distance within arange of about 1.5 in. to 3 in. In one embodiment, the distance W isabout 2.25 in. Other distances are contemplated. The distance H is thedistance from the web upper side 192 to the web lower side 194 and isless than the boss outer diameter D when measured between theintermediate portions 190 b and the outboard portions 190 a on the web190. Preferably, the distance H is less than one-half of the boss outerdiameter D. In this embodiment, distance H is about 40% of distance D,but it may vary. Distance H, which may be considered to be a verticaldimension of the forward face 200 of the web 190, may be the same in theweb outboard portions 190 a and the intermediate portions 190 b. FIG. 5illustrates the constant width of the web portions 190 a and 190 b.

Referring still to FIG. 4, the width P of the cylindrical base portion182 may be compared to the length of the protrusion L of each boss 178from the fluid end block forward face 160 to the boss forward end 178.In the exemplary embodiment shown, the ratio of L/P is about 1.867. Inother embodiments, the ratio of L/P is in the range of from about 1.750to about 1.944. In some embodiments, the width P may be a width within arange of about 0.5 in to 4 in., while in other embodiments, the width Pmay be a width within a range of about 1 in. to 2 in. In one embodiment,the width P is about 1.5 in. Other widths are contemplated.

In this embodiment, the upper fillet 204 and the lower fillet 210 have aconstant radius R from one outboard side 164 to the other. Preferably,the radius R is a dimension that is greater than one-half of thedistance W from the fluid end block forward side 160 to the web forwardface 200. In the exemplary embodiment, the radius R is about 60% ofdistance W, but the radius may vary. In some embodiments, the radius Rmay be a radius within a range of about 0 to 3 in., while in otherembodiments, the radius R may be a radius within a range of about 0 to1.38 in. In one embodiment, the radius R is about 0.38 in. Otherradiuses are contemplated.

Referring to FIG. 6, each boss 176 has a wall thickness T measured froma counterbore 212, which receives the packing 152, to base portion 182.In the embodiment shown, the thickness T over radius R is about 1.5. Inanother embodiment, the ratio T/R is in the range of from about 1.0 toabout 2.25.

Referring to FIG. 6, each plunger bore 150 has a counterbore 212 formedtherein for receiving the packing 152. The counterbore 212 results in aforward facing shoulder 214 that is abutted by a rearward end of thepacking 152. In this embodiment, the forward facing shoulder 214 islocated within the boss 176 and in a plane forward from the forward side160 of the fluid end block 104. The packing 152 may be a variety oftypes and contain a variety of different rings. As an example only, thepacking 152 may have a trash ring 216 at its rearward end that abuts theshoulder 214. The trash ring 216 does not seal pressure; rather itserves to exclude large particle debris from the remainder of thepacking 152. An energizing ring 218 may abut the forward side of thetrash ring 214. The energizing ring 218 also does not seal to theplunger 138; rather it energizes or deforms a main seal ring 220 intosealing engagement with the side wall of the counterbore 212 and theouter diameter of plunger 138. The main seal 220 is typically formed ofa rubber type of material softer than the energizing ring 218, and itmay have a concave rearward side and convex forward side. A hard plasticring 222 is located on the forward side of the main seal ring 220. Alantern ring 224, typically formed of brass, has a lubricant port (notshown) extending from its outer diameter to its inner diameter fordispensing lubricant to the plunger 138. Lubricant is supplied from alubricant passage (not shown) extending through the boss 176. One ormore forward rings 226 may be located on the forward side of the lanternring 224 to accommodate the rotation of the retainer nut 154 as it isbeing installed and to retard lubricant leaking out the forward end ofthe counterbore 212.

The retainer nut 154 has external threads 230 that engage the plungerbore threads 180. The retainer nut 154 has a rearward end 232 that abutsthe forward ring 226. Tightening the retainer nut 154 applies an axialcompressive force on the packing 152, which causes the main seal 220 tosealingly engage the outer diameter of the plunger 138. The outerdiameter of the plunger 138 does not slide against the bore of theretainer nut 154 or the plunger bore 150 because of the clearances beingprovided.

FIGS. 7-9 show another exemplary fluid end block referenced herein bythe numeral 300 consistent with the principles of the presentdisclosure. FIG. 7 is a perspective view, FIG. 8 is a front elevationview, and FIG. 9 is a cross-sectional view taken through the lines 9-9in FIG. 8. Referring to all three of these Figures, the fluid end block300, like the fluid end block 104 discussed above, may form a part ofthe fluid end 103 of the reciprocating pump 100 in FIG. 1. The fluid endblock 300 has many features similar to the fluid end block 104 describedabove, and much of the description above applies to the fluid end block300. To avoid repetition, not all the features will be re-described. Inthis exemplary embodiment, the fluid end block 300 includes a main bodyportion 302, a plurality of bosses 304, and a web portion 306.

The main body portion 302 includes a forward face or forward side 310, arearward side 312, outboard sides 314, a bottom 316, and a top 318. Theforward side 310 forms a relatively flat planar surface and as describedabove, includes two planar stepped recess portions 310 a, 310 b alongthe upper section, includes a curvilinear stepped recess portion 310 c,and includes a planar stepped recess portion 310 d along a bottomsection. In this embodiment, the stepped recess portions 310 a, 310 b,310 d are generally flat and may form planes parallel to the planeformed by the forward side 310. The curvilinear stepped recess portion310 c has an undulating profile 320 with an outboard portion 320 a, acircumferential portion 320 b, and an intermediate portion 320 c.

Still referring to FIG. 7, as can be seen the rearward side 312 alsoincludes a curvilinear portion 312 a that mirrors the curvilinearstepped recess portion 310 c. As such, it includes an undulating profile322 with an outboard portion 322 a, a circumferential portion 322 b, andan intermediate portion 322 c. The top surface 318 between the frontcurvilinear portion 310 a and the rearward curvilinear portion 312 atherefore has a width that increases and decreases along the length ofthe top surface 318.

In the exemplary embodiment shown, the top 318 has a plurality of accessports 326 formed therein that provide access to an internal cylinderchamber (described below). The access ports 326 enable communicationwith a high pressure tube extending from the pump to a manifold truckfor feeding to a well bore.

In this embodiment, the curvilinear portions 310 c, 312 a are in partconcentric with the access ports 326. More particularly, in theembodiments disclosed, the circumferential portions 320 b, 322 b areconcentric with the inner diameter of the access ports 324, and theintermediate portions 320 c, 322 c connect the respectivecircumferential portions. The undulating profiles 320, 322 are smoothlycurved to limit stress risers while still providing suitable strengthfor operation. They may also reduce the overall weight of the fluid endblock and may reduce material costs by removing unnecessary orover-engineered material.

As described above, the forward side 310 includes a plurality of tie rodholes 328 formed therein to receive tie rods (shown in FIG. 1)connecting the fluid end block to the power end 102 of the reciprocatingpump. In this embodiment the tie rod holes 328 are threaded and areconfigured to connect the main body portion 302 to the power end 102. Assuch, as the tie rods are tightened in place, the main body portion 302is pulled toward the power end of the reciprocating pump. Because theapplied loading is on the main body portion instead of the bosses orweb, the bosses and the web may be subject to less stress than when theplurality of bosses has flanges at their distal ends that connect to tierods.

The bosses 304 and the web portion 306 protrude from the forward side310 in the manner described above. Like the bosses 176 described above,the bosses 304 in FIGS. 7-9 are integrally formed with the main bodyportion 302 and include two outboard bosses and at least oneintermediate boss located between the two outboard bosses. Each boss 304is generally cylindrical in shape and includes a forward end 332 that isforward of the main body forward side 310. Each boss 304 has a plungerbore 334 extending into the main body portion 302 from the forward end332. In this embodiment, each boss 304 includes an optional cylindricalbase portion 336 that has a larger outer diameter than a cylindricalforward portion 338.

Referring to FIGS. 7-9, the web portion 306 is integrally formed on thefluid end forward side 310 and joins the bosses 304. Like the web 190described herein, the web 306 is a band that extends from one outboardside 314 to the other, and which protrudes from the fluid end blockforward side 310. The web 306 includes two outboard portions 306 a, eachof which extends from one of the outboard bosses to one of the outboardsides 314. The web 306 also has two intermediate portions 306 b, each ofwhich extends between the intermediate boss and the outboard bosses. Theweb 306 has an upper side 350 and a lower side 352 that have straight aswell as curvilinear portions. The web 306 has a forward face 354 that inthis embodiment is flat and parallel with the boss forward ends 332 andthe fluid end block forward side 310.

The upper side 350 and the lower side 352 each form curvilinear surfacesundulating between the tie rod holes 328 and the bosses 304. These upperand lower sides 350, 352 of the web 306 are formed to be substantiallyperpendicular to the face of the forward side 310. The upper side 350includes two outboard portions 350 a, each having an end joining one ofthe outboard sides 314, includes circumferential portions 350 bextending convexly partially around an upper portion of each boss 304,and includes intermediate portions 350 c each extending concavelybetween the upper circumferential portions 350 b. In the embodimentshown, the lower side 352 is a mirror image of the upper side andincludes two outboard portions 352 a, each having an end joining one ofthe outboard sides 314, includes circumferential portions 352 bextending convexly partially around an upper portion of each boss 304,and includes intermediate portions 352 c each extending concavelybetween the upper circumferential portions 350 b.

In some embodiments, the upper and lower circumferential portions 350 b,352 b are convexly curved surfaces concentric with the diameter of thebosses 304. In some embodiments, the intermediate portions 350 c, 352 care concavely curved surfaces concentric with the diameter of the tierod holes 328. In this example, the intermediate portions 350 b, 352 bextend about 90 degrees about a plunger axis 360, and thecircumferential portions 350 c, 352 c extend about 90 degrees about atie rod axis 362. In other embodiments, the profile of the upper andlower sides 350, 352 varies to be either greater or less than thatdescribed herein, depending upon the size and positions of the bosses304 and the tie rods holes 328. Furthermore, in some embodiments, theupper and lower sides 350, 352 are not mirror images of each other. Inthe embodiment shown in FIGS. 7-9, there are two upper intermediateportions 350 c, each extending from an end of the upper circumferentialportions 350 b to an end of the adjacent upper circumferential portion350 b.

In a manner similar to that described above with reference to the fluidend block 104, the fluid end block 300 includes an upper fillet 356 thatjoins the web upper side 350 to the fluid end forward side 310. Theupper fillet 356 is a curved surface extending continuously from oneoutboard side 314 to the other. The upper fillet 356 has two outboardportions 356 a, two circumferential portions 356 b, and two intermediateportions 356 c, formed in the manner described above. Likewise, thefluid end block 300 includes a lower fillet 358 joining the web lowerside 352 to the fluid end forward side 310. The lower fillet 358includes outboard portions 358 a, circumferential portions 358 b, andintermediate portions 358 c as described above.

In the example shown, the undulating design of the web portion 306provides stress relief and support to the bosses 304, while enabling thetie rods rod holes 328 to be disposed close in proximity to the bosses304 while still being formed in the forward face of the main body,rather than in a face of a surface offset from the forward face 310 ofthe main body portion 304. Attaching the tie rods to the main forwardsurface 310 of the main body portion 304 may reduce stress that mightotherwise be on the bosses because the bosses 304 are no longer theattachment elements of the fluid end to the power end of the pump.

The fluid end block 300 may be sized differently than the fluid endblock 104, but includes a distance L between the forward side 332 ofeach boss 304 and the forward surface 310, includes an outer diameter Dof the forward portion 338 of each boss 304, a web distance W betweenthe forward face 354 of the web 306 and the forward face 310 of the mainbody portion 302, a distance H from the web upper side 350 to the weblower side 352 and in the embodiments shown is less than the boss outerdiameter D at the intermediate portions 306 b of the web 306 and at theoutboard portions 306 a of the web 306. In addition, the fluid end block300 includes a length P representing the length of the cylindrical baseportion 336. The radius of the fillets 356, 358 may have a constantradius R and the bosses 304 have a wall thickness T. Dimensions for thevariables are discussed above with reference to the fluid end block 104.

The cross-section view in FIG. 9, taken along lines 9-9 in FIG. 8, showschambers and entrance and exit ports of the fluid end block 300 ingreater detail. For example, FIG. 9 shows a cylinder chamber 366, theplunger bore 334, a suction valve port 368, the access port 326 as adischarge port, and a second access port 370. In use, the suction valveport 368 communicates with a manifold and the access port 326communicates with a high pressure fluid line. The second access port 370receives a suction cover plate as shown in FIG. 1.

FIGS. 10 and 11 show another exemplary fluid end block referenced hereinby the numeral 400 consistent with the principles of the presentdisclosure. The fluid end block 400, like the fluid end blocks 104 and300 discussed above, may form a part of the fluid end 103 of thereciprocating pump 100 in FIG. 1. The fluid end block 400 has manyfeatures similar to the fluid end blocks 104 and 300 described above,and much of the description above applies to the fluid end block 400.Again, to avoid repetition, not all the features will be re-described. Aprimary difference between the fluid end block 400 and the fluid endblock 300 is that the fluid end block 300 has a triplex fluid end, as ithas three bosses with three bores, while the fluid end block 400 has aquint or a quintuplex fluid end, as it has five bosses with five bores.

As can be seen, the fluid end block 400 includes a main body portion402, a plurality of bosses 404, and a web portion 406. In all respectsexcept for the number of bosses and its impact on the sizes of variousfeatures of the fluid block, the discussion above applies to the fluidend block 400 in all respects.

In each of the embodiments described herein, the fluid end block mainbody portion, the bosses, and web are integrally formed with each other.That is, there are no welds or fasteners securing bosses and theportions of web to the fluid end block and each other. Accordingly, theyare formed from a monolithic material. The fluid end block, bosses, andthe portions of web are formed from a single-piece steel alloy forging,which remains a single piece after machining. Preferably, a single-piecesteel alloy forging is made having approximate dimensions for the fluidend block, including the main body, the bosses, and the web. The singlepiece forging may also have cavities with approximate dimensions for theplunger bores. Alternately, some of these features may be entirelymachined from the single-piece forging. The manufacturer then machinesthe single-piece forging into a single-piece member with the shape shownin the Figures herein. The machining operations will normally providethe final dimensions of the bosses, plunger bores, web, and fillets. Theplunger bore threads will also be formed. Then the packing and theplunger are inserted into each plunger bore and the separately machinedretainer nut is secured to the threads.

With the fluid end block now properly sized and shaped for installationon reciprocating pump, the fluid end may be transported to a power endof a reciprocation pump. The fluid end blocks described herein may beused to build a new pump or may be used to refurbish or repair a usedreciprocating pump. The fluid end block may be connected to a power endby inserting a plunger into the plunger bore of the pump so that theplunger passes through the retainer nut and the packing. With theplunger in place, tie rods may be used to connect to the tie rod holesin the forward side of the fluid end block. To do this, the tie rods maybe placed to extend past the bosses and past the web on the fluid faceto be received in the tie rod holes formed in the main body. They may bealigned to pass between the peaks or between the fillets on the web andinto the tie rod holes in the forward side, extending beyond the web andthe bosses, with the web being entirely devoid of tie rod holes. Withthe tie rods connected to the fluid end block, the tie rods may betightened to secure the fluid end block in place relative to the powerend. Since the tie rods bypass the bosses and bypass the web, the tierods do not apply direct tension loads on the web or bosses, reducingthe overall stress on the bosses and potentially increasing the usefullife of the fluid end block. At the same time, since the tie rods extendbetween parts of the web, either between peaks of the upper and lowersurface or between fillets on the web, the tie rods can be disposed inclose proximity to the web and bosses to provide stabilizing support asthe plunger pumps fluid to providing sufficient holding force tomaintain the fluid end block in place. With the fluid end block nowsecured to the power end of the reciprocating pump, the suction manifoldmay be connected to the fluid end block and the pump may be connected tothe manifold or additional tubing for use in a pumping application.

Operation is described below referring to FIG. 1. However, it should beunderstood that the discussion applies to any of the fluid end blocksdescribed herein. During operation, the plunger 138 reciprocates, ormoves longitudinally toward and away from the cylinder chamber 108, asthe crankshaft 122 rotates. As the plunger 138 moves longitudinally awayfrom the cylinder chamber 108, the pressure of the fluid inside thechamber 108 decreases, creating a differential pressure across the inletvalve 116, which actuates the valve 116 and allows the fluid to enterthe cylinder chamber 108 from the suction manifold 110. The fluid beingpumped enters the chamber 108 as the plunger 138 continues to movelongitudinally away from the cylinder chamber 108 until the pressuredifference between the fluid inside the cylinder chamber 108 and thefluid in the suction manifold 110 is small enough for the inlet valve116 to actuate to its closed position. As the plunger 138 begins to movelongitudinally towards the cylinder chamber 108, the pressure on thefluid inside the cylinder chamber 108 begins to increase. The fluidpressure inside the chamber 108 continues to increase as the plunger 138approaches the cylinder chamber 108 until the differential pressureacross the outlet valve 118 is large enough to actuate the valve 118 andallow the fluid to exit the cylinder chamber 108 through the dischargeport 112. In one embodiment, fluid is only pumped across one side of theplunger 138, therefore the reciprocating pump 100 is a single-actingreciprocating pump. Since the fluid end block main body, bosses and webare integrally formed with each other, there is a reduction of failurepoints and overall lower stress in the fluid end during operation ascompared to the conventional two part design requiring seals and packingglands. Moreover, the abrasion in the plunger bore is reduced using theintegrally formed fluid end block main body, bosses, and web as comparedto a conventional two part design.

In some exemplary embodiments, variations may be made to the fluid endblocks. In several exemplary embodiments, instead of, or in addition tobeing used in high pressure reciprocating pumps, the fluid end blocks orthe components thereof may be used in other types of pumps and fluidsystems.

In the foregoing description of certain embodiments, specificterminology has been resorted to for the sake of clarity. However, thedisclosure is not intended to be limited to the specific terms soselected, and it is to be understood that each specific term includesother technical equivalents which operate in a similar manner toaccomplish a similar technical purpose. Terms such as “left” and right”,“front” and “rear”, “above” and “below” and the like are used as wordsof convenience to provide reference points and are not to be construedas limiting terms.

In this specification, the word “comprising” is to be understood in its“open” sense, that is, in the sense of “including”, and thus not limitedto its “closed” sense, that is the sense of “consisting only of”. Acorresponding meaning is to be attributed to the corresponding words“comprise”, “comprised” and “comprises” where they appear.

In addition, the foregoing describes only some embodiments of theinvention(s), and alterations, modifications, additions and/or changescan be made thereto without departing from the scope and spirit of thedisclosed embodiments, the embodiments being illustrative and notrestrictive.

Furthermore, invention(s) have described in connection with what arepresently considered to be the most practical and preferred embodiments,it is to be understood that the invention is not to be limited to thedisclosed embodiments, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the invention(s). Also, the various embodiments described abovemay be implemented in conjunction with other embodiments, e.g., aspectsof one embodiment may be combined with aspects of another embodiment torealize yet other embodiments. Further, each independent feature orcomponent of any given assembly may constitute an additional embodiment.

What is claimed is:
 1. A fluid end block for attachment to a power end of a high pressure reciprocating pump, comprising: a main body portion having a plurality of chambers therein, the main body portion having an outwardly facing body forward face, an outwardly facing body rear face opposite the body forward face, and opposing side surfaces connecting the forward face and the rear face; a web portion protruding outwardly from the outwardly facing body forward face, the web portion having an outwardly facing web forward face and a curvilinear side surface, the web portion being integral with the main body portion; a plurality of bosses protruding from the web forward face and having a forward facing end, the plurality of bosses being integral with the main body portion and the web portion; and a plunger bore extending through one of the plurality of bosses configured to receive a reciprocating plunger, the plunger bore extending from the end of said one of the plurality of bosses to one of the plurality of chambers in the main body portion.
 2. The fluid end block of claim 1, wherein the curvilinear side surface comprises a convex portion concentric with each of the plurality of bosses.
 3. The fluid end block of claim 2, wherein the convex portion has a radius greater than a radius of each of the plurality of bosses.
 4. The fluid end block of claim 1, wherein the main body portion comprises a tie rod hole disposed adjacent the web portion, the tie rod hole being disposed between undulating portions of the web portion.
 5. The fluid end block of claim 4, wherein the curvilinear side surface comprises a concave portion concentric with a diameter of the tie rod hole.
 6. The fluid end block of claim 4, wherein the undulating portions are a portion of the curvilinear side surface.
 7. The fluid end block of claim 4, wherein the undulating portions is a part of a fillet connecting the curvilinear side surface of the web portion to the body forward face.
 8. The fluid end block of claim 1, wherein each of the plurality of bosses has a first length measured from the web forward face to the end of the boss, and wherein the web portion has a second length measured from the body forward face to the web forward face, the first length being greater than the second length.
 9. The fluid end block of claim 1, wherein the web portion extends across the body forward face from one of the opposing side surfaces to the other.
 10. The fluid end block of claim 1, wherein the plurality of bosses are aligned in a row so that a single plane passes through a central axis formed by each of the plurality of bosses.
 11. The fluid end block of claim 1, wherein the curvilinear side surface of the web portion is perpendicular to the body forward face and perpendicular to the web forward face.
 12. The fluid end block of claim 1, wherein each of the plurality of bosses comprises an outer surface portion having a first diameter adjacent the forward facing end and having a second diameter adjacent the web portion, the second diameter being greater than the first diameter.
 13. The fluid end block of claim 1, wherein the curvilinear side surface is an upper side surface, the fluid end block comprising a curvilinear lower side surface, wherein the curvilinear upper side surface mirrors the curvilinear lower side surface.
 14. A pump assembly comprising: the fluid end block of claim 1; and a power end including a reciprocating plunger extending into the plunger bore.
 15. The pump assembly of claim 14, comprising tie rods extending from the power end, past the plurality of bosses, past the web portion, and into tie rod holes in the forward face of the main body portion.
 16. A fluid end block for attachment to a power end of a high pressure reciprocating pump, comprising: a main body portion having a plurality of chambers therein, the main body portion having an outwardly facing body forward face, an outwardly facing rear face opposite the body forward face, and opposing side surfaces connecting the body forward face and the rear face; a plurality of bosses supported by the main body portion and having a forward facing end, the plurality of bosses being integral with the main body portion and having an outer diameter at the forward facing end; a web portion protruding outwardly from the outwardly facing body forward face of the main body portion, the web portion having a longitudinal length and a transverse height, the web portion joining each of the plurality of bosses to each other, the transverse height of the web portion being greater than the outer diameter of the plurality of bosses; and a plunger bore extending through one of the plurality of bosses configured to receive a reciprocating plunger, the plunger bore extending from the end of said one of the plurality of bosses to one of the plurality of chambers in the main body portion.
 17. The fluid end block of claim 16, wherein the web portion comprises a curvilinear side surface comprising a convex portion concentric with each of the plurality of bosses.
 18. The fluid end block of claim 17, wherein the convex portion of the web portion has a radius greater than a radius of each of the plurality of bosses.
 19. The fluid end block of claim 16, wherein the main body portion comprises a tie rod hole disposed adjacent the web portion, the tie rod hole being disposed between undulating portions of the web portion.
 20. The fluid end block of claim 19, wherein the undulating portions are formed of a curvilinear side portion comprising a concave portion concentric with a diameter of the tie rod hole.
 21. The fluid end block of claim 19, wherein the undulating portions are a curvilinear side surfaces.
 22. The fluid end block of claim 19, wherein the undulating portions is a part of a fillet connecting a curvilinear side surface of the web to the body forward face.
 23. The fluid end block of claim 16, wherein each of the plurality of bosses has a first length measured from the web forward face to the end of the boss, and wherein the web portion has a second length measured from the body forward face to the web forward face, the first length being greater than the second length.
 24. The fluid end block of claim 16, wherein the web portion extends entirely across the body forward face from one of the opposing side surfaces to the other.
 25. The fluid end block of claim 16, wherein the plurality of bosses are aligned in a row so that a single plane passes through a central axis formed by each of the plurality of bosses.
 26. The fluid end block of claim 16, wherein the web portion comprises upper and lower side surfaces and a web forward face, the upper and lower side surfaces being perpendicular to the body forward face and perpendicular to the web forward face.
 27. The fluid end block of claim 16, wherein each of the plurality of bosses comprises an outer surface portion having a first diameter adjacent the forward facing end and a second diameter adjacent the web portion, the second diameter being greater than the first diameter.
 28. The fluid end block of claim 16, wherein the web portion comprises curvilinear upper and lower side surfaces and a web forward face, wherein the curvilinear upper side surface mirrors the curvilinear lower side surface.
 29. A pump assembly comprising: the fluid end block of claim 16; and a power end including a reciprocating plunger extending into the plunger bore.
 30. The pump assembly of claim 29, comprising tie rods extending from the power end, past the plurality of bosses, past the web portion, and into tie rod holes in the forward face of the main body portion.
 31. A fluid end block for attachment to a power end of a high pressure reciprocating pump, comprising: a main body portion having an outwardly facing body forward face, an outwardly facing rear face opposite the body forward face, and opposing side surfaces connecting the body forward face and the rear face, the main body portion comprising a plurality of tie rod holes configured to receive tie rods connecting the fluid end block to the power end of a high pressure reciprocating pump; a web portion protruding outwardly from the body forward face of the main body portion, the web portion having an curvilinear portion adjacent the tie rod holes, the curvilinear portion being shaped and disposed so that at least one of the tie rod holes is disposed between peaks of the curvilinear portion, the web portion being integrally formed with the main body portion; a plurality of bosses on the web portion, the plurality of bosses being integrally formed with the web portion and the main body portion; and a plunger bore extending through one of the plurality of bosses configured to receive a reciprocating plunger.
 32. The fluid end block of claim 31, wherein the curvilinear portion comprises a convex portion concentric with each of the plurality of bosses.
 33. The fluid end block of claim 32, wherein the convex portion has a radius greater than a radius of each of the plurality of bosses.
 34. The fluid end block of claim 31, wherein the curvilinear portion comprises a concave portion concentric with a diameter of the tie rod hole.
 35. The fluid end block of claim 31, wherein the curvilinear portion comprises a curvilinear side surface.
 36. The fluid end block of claim 31, wherein the curvilinear portion comprises a fillet connecting a side surface of the web portion to the body forward face.
 37. The fluid end block of claim 31, wherein each of the plurality of bosses has an end and the web portion has a forward face, each of the plurality of bosses having a first length measured from the web forward face to the end of the boss, and the web portion having a second length measured from the body forward face to the web forward face, the first length being greater than the second length.
 38. The fluid end block of claim 31, wherein the web portion extends entirely across the body forward face from one of the opposing side surfaces to the other.
 39. The fluid end block of claim 31, wherein the plurality of bosses are aligned in a row so that a single plane passes through a central axis formed by each of the plurality of bosses.
 40. The fluid end block of claim 31, wherein the curvilinear portion comprises a side surface of the web portion perpendicular to the body forward face.
 41. The fluid end block of claim 31, wherein each of the plurality of bosses comprises an outer surface portion having a first diameter adjacent the forward facing end and a second diameter adjacent the web portion, the second diameter being greater than the first diameter.
 42. The fluid end block of claim 31, wherein the curvilinear portion comprises a curvilinear upper side surface and a curvilinear lower side surface, wherein the curvilinear upper side surface mirrors the curvilinear lower side surface.
 43. The fluid end block of claim 31, wherein the web portion is devoid of tie rod receiving holes.
 44. A fluid pump comprising: the fluid end block of claim 31; and tie rods extending to the main body so that the bosses are not held in tension.
 45. A method of manufacturing a fluid end for a pump, comprising: forming from a monolith material, a main body portion having an outwardly facing body forward face, an outwardly facing body rear face opposite the body forward face, and opposing side surfaces connecting the forward face and the rear face; forming from the monolith material, a web portion protruding outwardly from the outwardly facing body forward face, the web portion having an outwardly facing web forward face and a curvilinear side surface; forming from the monolith material, a plurality of bosses protruding from the web forward face and having a forward facing end; and forming a plunger bore extending through one of the plurality of bosses configured to receive a reciprocating plunger.
 46. The method of claim 45, wherein forming the web portion comprises shaping the curvilinear side surface to have a convex portion concentric with each of the plurality of bosses.
 47. The method of claim 45, comprising forming a tie rod hole in a location adjacent the web portion so that the tie rod hole is disposed between undulating portions of the web portion.
 48. A fluid end block for attachment to a power end of a high pressure reciprocating pump, comprising: a main body portion having a plurality of chambers therein, the main body portion having an outwardly facing body forward face, an outwardly facing rear face opposite the body forward face, and opposing side surfaces connecting the body forward face and the rear face, the main body portion comprising a plurality of tie rod holes configured to receive tie rods connecting the fluid end block to a power end of a high pressure reciprocating pump; a web portion protruding outwardly from the outwardly facing body forward face, the web portion having an outwardly facing web forward face, an upper curvilinear side surface, and a lower curvilinear side surface mirroring the upper curvilinear side surface, the upper and lower curvilinear side surfaces having convex and concave portions, the web portion extending continuously from one of the opposing side surfaces of the main body portion to the other, and being integrally formed with the main body portion; a plurality of bosses protruding from the web forward face and having a forward facing end, each of the plurality of bosses having an end, a first region of a first diameter adjacent the end, and a second region of a second diameter adjacent the web portion, the second diameter being greater than the first diameter, the plurality of bosses being integral with the main body portion and the web portion, and wherein the convex portions of the upper and lower curvilinear side surfaces are concentric with the second region of each of the plurality of bosses, and wherein the concave portions of the upper and lower curvilinear side surfaces accommodate the tie rod holes so that the tie rod holes are disposed between portions of the web portion; and a plunger bore extending through one of the plurality of bosses configured to receive a reciprocating plunger, the plunger bore extending from the end of one of the plurality of bosses to one of the plurality of chambers in the main body portion.
 49. The fluid end block of claim 48, wherein the tie rod holes are disposed between portions of a fillet connecting the curvilinear side surface of the web portion to the body forward face.
 50. The fluid end block of claim 49, wherein the tie rod holes are disposed between portions of the curvilinear upper side surface of the web portion.
 51. The fluid end block of claim 48, wherein the concave portions of the curvilinear upper and lower side surfaces are concentric with a diameter of the tie rod holes.
 52. The fluid end block of claim 48, wherein each of the plurality of bosses has a first length measured from the web forward face to the end of the boss, and wherein the web portion has a second length measured from the body forward face to the web forward face, the first length being greater than the second length.
 53. The fluid end block of claim 48, wherein the curvilinear side surface of the web portion is perpendicular to the body forward face and perpendicular to the web forward face.
 54. A pump assembly comprising: the fluid end block of claim 45; and a power end including a reciprocating plunger extending into the plunger bore.
 55. The pump assembly of claim 54, comprising tie rods extending from the power end, past the plurality of bosses and past the web portion and into tie rod holes in the forward face of the main body portion.
 56. A pump subassembly, comprising: a fluid end block having forward and rearward sides; a plurality of bosses protruding in a forward direction from the forward side, the fluid end block and the bosses being a single-piece steel alloy member; a plunger bore extending into the fluid end block from each of the bosses for receiving a reciprocating plunger, each of the plunger bores having a forward end with a set of internal threads; and a plurality of webs protruding from the forward side and joining adjacent ones of the bosses to each other.
 57. The pump subassembly according to claim 56, wherein the webs are an integral part of the single-piece steel alloy member along with the bosses and the fluid end block; and wherein each of the webs having an upper side and a lower side and a dimension between the upper and lower sides that is no greater than an outer diameter of each of the bosses.
 58. The pump subassembly according to claim 57, wherein a horizontal line bisecting each of the webs also intersects an axis of each of the plunger bores.
 59. The pump subassembly according to claim 56, further comprising: a fillet joining a base of each of each of the bosses with the forward side of the fluid end block; wherein a wall thickness of each of the bases from the base to the counter bore over the radius of each of the fillets is in a range of from about 1.0 to about 2.25.
 60. The pump subassembly according to claim 57, further comprising: a web upper fillet joining the upper side of each of the webs with the forward side of the fluid end block; a web lower fillet joining the lower side of each of the webs with the forward side of the fluid end block; a boss upper fillet extending partially around each of the bosses and joining an upper circumferential portion of each of the bosses with the forward side of the fluid end block, each of the boss upper fillets having an end that joins an end of one of the web upper fillets, such that the web upper fillets and the boss upper fillets define a continuous upper fillet extending across the bosses; and a boss lower fillet extending partially around each of the bosses and joining a lower circumferential portion of each of the bosses with the forward side of the fluid end block, each of the boss lower fillets having an end that joins an end of one of the web lower fillets, such that the web lower fillets and the boss lower fillets define a continuous lower fillet extending across the bosses.
 61. The pump subassembly according to claim 57, wherein each of the webs has a forward side that is a distance from the forward side of the fluid end block that is less than a distance from a forward end of each of the bosses to the forward side of the fluid end block.
 62. The pump subassembly according to claim 57, wherein: each of the bosses has a cylindrical forward end portion extending from a cylindrical base having a diameter greater than a diameter of the forward end portion; and a distance from a forward end of each of the bosses. to the forward side of the fluid end block over a width of the base is in the range of from about 1.750 to about 1.944.
 63. The pump subassembly according to claim 56, wherein: the bosses comprise an outboard boss adjacent to each outboard side of the fluid end block and at least one intermediate boss located between the outboard bosses; and the fluid end. block further comprises: a pair of outboard webs, each outboard web extending from one of the outboard bosses to one of the outboard sides of the fluid end; and each of the outboard webs having an upper side and a lower side and a dimension between the upper and lower sides that is no greater than an outer diameter of each of the outboard bosses.
 64. The pump subassembly according to claim 56, further comprising: a plurality of stay rod threaded holes extending into the fluid end block from the forward side; and wherein the forward end of each of the bosses is located forward from an entrance of each of the stay rod threaded holes.
 65. A pump subassembly, comprising: a fluid end block having forward and rearward sides, two outboard sides, a bottom, and a top; a plurality of bosses protruding in a forward direction from the forward side, the bosses comprising an outboard boss adjacent each of the outboard sides, and at least one intermediate boss located between the outboard bosses; a plunger bore extending into the fluid end block from each of the bosses for receiving a reciprocating plunger, each of the plunger bores having a forward end with internal threads; a web extending from the forward side of the fluid end block, the web having an outboard portion extending from each of the outboard sides to each of the outboard bosses, the web having an intermediate portion extending between adjacent ones of the bosses; the web having an upper side and a lower side, with a dimension between the upper and lower sides that is less than an outer diameter of any one of the bosses; and wherein the fluid end block, the bosses and the webs are integrally joined to each other and comprise a single-piece member formed of a steel alloy.
 66. The subassembly according to claim 65, wherein: the web has a forward face that is located forward from the forward side of the fluid end block a distance that is less than a distance from the forward end of each of the bosses to the forward side of the fluid end block.
 67. The subassembly according to claim 65, further comprising: a continuous upper fillet extending without interruption from one of the outboard sides to the other of the outboard sides, the upper fillet joining the upper sides of the web to the forward side of the fluid end block and joining upper circumferential portions of the bosses to the forward side; and a continuous lower fillet extending without interruption from one of the outboard sides to the other of the outboard sides, the lower fillet joining the tower sides of the web to the forward side of the fluid end block and joining lower circumferential portions of the bosses to the forward side.
 68. The subassembly according to claim 65, wherein: each of the plunger bores has a counter bore for receiving a packing; each of the bosses has a wall thickness measured from a base of the boss to the counter bore; and a ratio of the wall thickness over a radius of each of the fillets is in a range of from about 1.0 to about 2.25.
 69. A well service pump, comprising: a power end having a crankshaft and a plurality of connecting rods; a fluid end block having forward and rearward sides, two outboard sides, a bottom, and a top; a plurality of bosses protruding in a forward direction from the forward side of the fluid end block, the bosses comprising an outboard boss adjacent each of the outboard sides, and at least one intermediate boss located between the outboard bosses; a web extending from the forward side of the fluid end block, the web having an outboard portion extending from each of the outboard sides to each of the outboard bosses, the web having an intermediate portion extending between adjacent ones of the bosses; a plunger bore extending into the fluid end block from each of the bosses, each of the plunger bores having a forward end with internal threads; a plurality of plungers, each of the plungers being operably coupled to one of the connecting rods for stroking movement within one of the plunger bores; a packing surrounding each of the plungers within each of the plunger bores; an externally threaded retainer nut that engages the internal threads of each of the plunger bores for energizing each of the packings; a plurality of stay rods extending from the power end to threaded holes foamed in the forward side of the fluid end block, the threaded holes having entrances spaced a distance rearward from forward ends of the bosses; and wherein the fluid end block and the bosses are integrally joined to each other and comprise a single-piece member formed of a steel alloy.
 70. The pump according to claim 69, wherein the web has an upper side and a lower side with a dimension between the upper and lower sides that is less than an outer diameter of any one of the bosses; and wherein the web is integrally joined to the fluid end block and the bosses and forms a part of the single-piece member formed of a steel alloy.
 71. The pump according to claim 69, further comprising: a continuous upper fillet extending without interruption from one of the outboard sides to the other of the outboard sides, the upper fillet joining the upper sides of the web to the forward side of the fluid end block and joining upper circumferential portions of the bosses to the forward side of the fluid end block; and a continuous lower fillet extending without interruption from one of the outboard sides to the other of the outboard sides, the lower fillet joining the lower sides of the web to the forward side and joining lower circumferential portions of the bosses to the forward side of the fluid end block.
 72. A method of manufacturing a fluid end assembly of a reciprocating well service pump, comprising: (a) providing a single-piece forging of a steel alloy with a plurality of bosses protruding from a forward side of the single-piece forging, and providing a web in the single-piece forging extending between adjacent ones of the bosses and from outboard ones of the bosses to outboard sides of the single-piece forging, and (b) machining the single-piece forging into a configuration of a fluid-end block with a plunger bore having internal threads in each of the bosses.
 73. The method according to claim 72, wherein each of the webs having an upper side and a lower side with a distance between the upper and lower sides being less than an outer diameter of each of the bosses.
 74. The method according to claim 73, wherein step (a) further comprises: providing the single-piece forging with a continuous upper fillet extending without interruption from one of the outboard sides to the other of the outboard sides of the single-piece forging, the upper fillet joining the upper sides of the web to the forward side of the single-piece forging and joining upper circumferential portions of the bosses to the forward side of the single-piece forging; and providing the single-piece forging with a continuous lower fillet extending without interruption from one of the outboard sides to the other of the outboard sides, the lower fillet joining the lower sides of the web to the forward side of the single-piece forging and joining lower circumferential portions of the bosses to the forward side of the single-piece forging. 